<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        body{
            background-color: rgb(130, 168, 168);
        }
        div{
            /* background-image: url(17.jpg); */
            background-image: url(17.jpg);
            background-repeat: no-repeat;
            width: 1200px;
            height: 1000px;
            background-position: 0%;
            /* background-size: 700px 300px; */
            /* background-size: cover; */
            background-size: contain;
        }
        
    </style>
</head>
<body>
    <div>
        这是背景
    </div>
</body>
</html>